A tray feeder is known as a kind of parts feeder that supplies components such as semiconductor chips in a component mounting device. The tray feeder is formed so that palettes which hold trays in which components are stored are respectively accommodated in a plurality of palette accommodating parts which are provided in parallel at multiple levels from top to bottom. In a component mounting operation, these palettes are drawn out in accordance with a mounting order and moved to a component takeout position. When the components of the tray in a palette are used up, the palette whose components are used up is moved to a palette carrying part which is provided in an area different from the palette accommodating parts, and a tray exchange operation is performed in which the tray is exchanged with a new tray (for example, refer to a patent document 1). In the related art shown in this patent document, by temporarily accommodating new palettes for exchange in unoccupied palette accommodating parts in the plurality of palette accommodating parts, even if the palette whose components are used up is accommodated in the palette accommodating part as it is, the palette can be exchanged with a palette which holds a tray in which new components of the same type are stored.